CVE-2026-25905

Description

The Python code being run by runPython or runPythonAsync is not isolated from the rest of the JS code, allowing any Python code to use the Pyodide APIs to modify the JS environment. This may result in an attacker hijacking the MCP server - for malicious purposes including MCP tool shadowing. Note - the mcp-run-python project is archived and unlikely to receive a fix.

Risk Information

Base Score

5.8

MODERATE

Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L

EPSS Score

Exploitation Probability

0.011

Associated Vulnerability

Vulnerability	OS Platform
Vulnerabilities CVE-2026-25904,CVE-2026-25905 are affected in Python-mcp-run-python 0.0.22	Windows
Vulnerabilities CVE-2026-25904,CVE-2026-25905 are affected in Python-mcp-run-python for linux 0.0.22	Linux

Patch Details

No records found

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234